Question

Uncertainty in position of a particle of $25 g$ in space is $10^{-5} m$. Hence, uncertainty in velocity$\left( ms ^{-1}\right) $ is (Planck's constant $ h=6.6 \times 10^{-34} Js ) : $

• A. $2.1 \times 10^{-28}$
• B. $2.1 \times 10^{-34}$
• C. $0.5 \times 10^{-34}$
• D. $5.0 \times 10^{-24}$

Answer 1

Answer: (A)

Heisenberg uncertainty principle

$\Delta x \cdot m \Delta v \approx \frac{h}{4 \pi}$

uncertainty in velocity

$\Delta v =\frac{h}{4 \times 3.14 \times \Delta x \times m} $

$=\frac{6.626 \times 10^{-34}}{4 \times 3.14 \times 0.025 \times 10^{-5}} $

$=2.1 \times 10^{-28}$